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4x-3(5x+8)<_-7 inequation

A inequation with variable

The solution

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4*x - 3*(5*x + 8) <= -7
4x3(5x+8)74 x - 3 \left(5 x + 8\right) \leq -7
4*x - 3*(5*x + 8) <= -7
Detail solution
Given the inequality:
4x3(5x+8)74 x - 3 \left(5 x + 8\right) \leq -7
To solve this inequality, we must first solve the corresponding equation:
4x3(5x+8)=74 x - 3 \left(5 x + 8\right) = -7
Solve:
Given the linear equation:
4*x-3*(5*x+8) = -7

Expand brackets in the left part
4*x-3*5*x-3*8 = -7

Looking for similar summands in the left part:
-24 - 11*x = -7

Move free summands (without x)
from left part to right part, we given:
11x=17- 11 x = 17
Divide both parts of the equation by -11
x = 17 / (-11)

x1=1711x_{1} = - \frac{17}{11}
x1=1711x_{1} = - \frac{17}{11}
This roots
x1=1711x_{1} = - \frac{17}{11}
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
x0x1x_{0} \leq x_{1}
For example, let's take the point
x0=x1110x_{0} = x_{1} - \frac{1}{10}
=
1711+110- \frac{17}{11} + - \frac{1}{10}
=
181110- \frac{181}{110}
substitute to the expression
4x3(5x+8)74 x - 3 \left(5 x + 8\right) \leq -7
(181)41103((181)5110+8)7\frac{\left(-181\right) 4}{110} - 3 \left(\frac{\left(-181\right) 5}{110} + 8\right) \leq -7
-59       
---- <= -7
 10       

but
-59       
---- >= -7
 10       

Then
x1711x \leq - \frac{17}{11}
no execute
the solution of our inequality is:
x1711x \geq - \frac{17}{11}
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       x1
Solving inequality on a graph
501234-6-5-4-3-2-1-100100
Rapid solution [src]
   /-17              \
And|---- <= x, x < oo|
   \ 11              /
1711xx<- \frac{17}{11} \leq x \wedge x < \infty
(-17/11 <= x)∧(x < oo)
Rapid solution 2 [src]
 -17      
[----, oo)
  11      
x in [1711,)x\ in\ \left[- \frac{17}{11}, \infty\right)
x in Interval(-17/11, oo)